/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: mirac
 * Date: 2025-08-08
 * Time: 22:38
 */
public class Solution {
    public boolean hasCycle(ListNode head) {
        ListNode slow = head;
        ListNode fast = head;
        while (fast != null && fast.next != null) {
            fast = fast.next.next;
            slow = slow.next;
            if (fast == slow) {
                return true;
            }
        }
        return false;
    }
}
